fan/accel: gate accel logger on openpilotLongitudinalControl

The accel logger only exists to inform accel-eq's max-accel tuning, and accel-eq
only affects the car when OP has longitudinal control. On a stock-long car it was
pointlessly logging the driver to a CSV (with periodic flash writes) for data
that can never be applied. Skip logging entirely when not CP.openpilotLongitudinalControl.

dragonpilot/selfdrive/controls/lib/accel_logger.py

@@ -55,6 +55,7 @@ class AccelLogger:
 
   def __init__(self, CP, path=None):
     self._CP = CP
+    self._enabled = CP.openpilotLongitudinalControl  # accel-eq only applies under OP long
     self._path = path if path is not None else LOG_PATH
     self._buf = []
     self._frames = 0
@@ -71,6 +72,8 @@ class AccelLogger:
       cloudlog.warning(f"AccelLogger: write failed (dropped {len(rows)} rows): {e}")
 
   def update(self, sm):
+    if not self._enabled:
+      return
     try:
       self._frames += 1
       cs = sm['carState']

dragonpilot/selfdrive/controls/lib/tests/test_accel_logger.py

@@ -26,7 +26,7 @@ def test_each_condition_blocks():
 
 
 DRIVE = car.CarState.GearShifter.drive
-CP = SimpleNamespace(steerRatio=15.0, wheelbase=2.7)
+CP = SimpleNamespace(steerRatio=15.0, wheelbase=2.7, openpilotLongitudinalControl=True)
 
 def _sm(**over):
     cs = dict(vEgo=10.0, aEgo=0.8, gasPressed=True, brakePressed=False,
@@ -51,6 +51,13 @@ def test_gate_blocks_dirty_sample(tmp_path):
     log.update(sm)
     assert log._buf == []
 
+def test_no_op_long_disables_logging(tmp_path):
+    # stock-long car: accel-eq is inert, so the logger must not run at all
+    stock_cp = SimpleNamespace(steerRatio=15.0, wheelbase=2.7, openpilotLongitudinalControl=False)
+    log = AccelLogger(stock_cp, path=str(tmp_path / "h.csv"))
+    log.update(_sm(vEgo=10.0, aEgo=0.8))  # would be a clean sample under OP long
+    assert log._buf == []
+
 def test_in_curve_sample_rejected_end_to_end(tmp_path):
     # large steering -> lateral accel exceeds LAT_ACCEL_MAX -> not buffered
     log = AccelLogger(CP, path=str(tmp_path / "h.csv"))